Computers allow us to squeeze the most out of everything, whether it's Google looking up things, so I guess that tends to make us a little lazy about reading books and doing things the hard way to understand how those things work.

Drive over to the nearest airport, and enroll in flight classes. You will experience the joy of freedom in the air above, as you study the mechanics of how this is made possible by understanding the construction, the laws of motion, the air that can provide lift when it is moved by propulsion through the air, and stay above the gravity pulling the airplane back down to earth.

As time goes by, I'm increasingly impressed by how very special and timely it was that we got the degree of national commitment needed to put people on the Moon. For the first time, this nation was united in trying to develop an interplanetary capability. We've been trying to repeat that situation ever since.

I was the first Navy, Marine or Air Force person who had been an astronaut to return back to the Air Force. I had certain expectations about what would be a reasonable and desirable position to be assigned to after my years of service.

Most people never believed in the real possibility of going to the moon, and neither did I until I was in my twenties.

Mars is the symbolic and totally stimulating next objective that could so dominate the next century's exploration efforts. From Mars, the resources of all the asteroids will become readily available.

There's a tremendously satisfying freedom associated with weightlessness. It's challenging in the absence of traction or leverage, and it requires thoughtful readjustment. I found the experience of weightlessness to be one of the most fun and enjoyable, challenging and rewarding, experiences of spaceflight. Returning to Earth brings with it a great sense of heaviness, and a need for careful movement. In some ways it's not too different from returning from a rocking ocean ship.